EPID-10. THE INCIDENCE OF PRIMARY BRAIN TUMORS IN JAPAN IN 2016-2019

Abstract The national cancer registries in Japan have started since 2016 and the actual number of cancer patients in including primary central nervous system (CNS) tumors in Japan was revealed. Average number of primary CNS tumors in 2016-2019 was 29,492 and the crude incidence rate per 100,000 people (CIR) was 23.30. Malignant and benign CNS tumors was 6,696 (22.7%) and 22,796 (77.3%) and each CIR was 5.29 and 18.00, respectively. Among 29,492 tumors, 10,537 (35.7%) meningioma, 5,217 (17.7%) pituitary adenoma, 4,537 (15.4%) neuroepithelial tumor, 2,730 (9.3%) neurinoma and 1,166 (4.0%) primary CNS lymphoma (PCNSL) were reported. Regarding to malignant brain tumors, 2,071 glioblastoma, 362 astrocytoma grade II, 390 anaplastic astrocytoma grade III, 138 pilocytic astrocytoma,182 oligodendroglioma grade II, 154 anaplastic oligodendroglioma grade III, 140 ependymal tumors, 128 embryonal tumors including 91 medulloblastoma, 211 germ cell tumor (GCT) were found. CIR of neuroepithelial tumor, glioblastoma, PCNSL, embryonal tumors and GCT were 3.64, 1.68, 0.93, 0.10 and 0.17, respectively. According to the Central Brain Tumor Registry of the United States (CBTRUS) (2016-2020), CIR in the US was 26.73, and age-adjusted incidence rates of primary CNS tumors per 100,000 population in the US based on the US population in 2000 (AIR) was 24.83 and AIR in Japan was 17.15. AIR of glioblastoma in the US and Japan was 3.27 and 1.05, AIR of PCNSL was 0.44 and 0.51, AIR of embryonal tumors was 0.21 and 0.16, AIR of GCTs was 0.08 and 0.27, and AIR of meningioma was 9.73 and 5.11, respectively. This report demonstrated that the incidence of neuroepithelial tumors and embryonal tumors in Japan was approximately half to one-third, whereas that of GCTs in Japan was approximately 3 times comparing to the US.